Spark advance mechanism for ignition distributors of internal combustion engines

ABSTRACT

An ignition distributor for internal combustion engines wherein the angular position of the breaker plate with respect to the shaft can be changed by a spark advance mechanism employing a two-armed displacing lever pivotable about a fixed axis and having one of its arms connected to the breaker plate by a pinand-slot connection. The other arm of the displacing lever carries a pivotable two-armed motion transmitting lever one arm of which is articulately connected to the output member of a first adjusting unit and the other arm of which is articulately connected to the output member of a second adjusting unit. The displacing lever changes the angular position of the breaker plate when the motion transmitting lever is pivoted by one or both adjusting units. Each adjusting unit comprises one or more discrete adjusting devices in the form of vacuum chambers, electromagnets, Bowden wires or the like.

United States Patent Heine 5/1934 United Kingdom 123/117 A 3/1921 France 123/117 A [75] Inventor: Joseph Heine, Leonberg, Germany Primary Examiner-Charles J. Myhre Assistant Examiner-Tony Argenbright [73] Asslgnee. Robert Bosch G.m.b.H., Stuttgart, Attorney, Agent, or Firm Michael S. striker Germany [22] Filed: Oct. 3, 1973 [21] Appl. No.: 403,171 [57] ABSTRACT An ignition distributor for internal combustion engines [30] Foreign Apphcauon Pnomy Data wherein the angular position of the breaker plate with Oct. 6, 1972 Germany 2249128. respect to the Shaft can be changed by a spark vance mechanism employing a two-armed displacing [52] US. Cl. 123/117 A; 123/1 17 R lever pivotable about a fixed axis and having one of its [51] Int. Cl. F02p 5/10 arms connected to the breaker plate by a i [58] held M Search 23/117 117 1465 A connection. The other arm of the displacing lever carries a pivotable two-armed motion transmitting .1561 References C'ted lever one arm of which is articulately connected to the UNITED STATES PATENTS output member of a first adjusting unit and the other 1,818,079 8/1931 Meade 123/117 A arm of which is articulately Connected to the Output 1,845,818 2/1932 Spiller 123/117 A member of a second adjusting unit. The displacing 2,378,037 /19 5 Reggie 123/1l7 A lever changes the angular position of the breaker plate ,1 6 12/1945 Parkins et a1..... 123/117 A when the motion transmitting lever is pivoted by one 2,698,010 2/1954 Hartman, et a1 123/1 A Or both adjusting units. Each adjusting unit comprises w i' 5 5 2 one or more discrete adjusting devices in the form of a er 3,727,596 4/1973 Panhard.... 123/117 R x f f chambers electmmagnets Bowde" 3,735,743 5/1973 Shimizu 123/117 A t e l FOREIGN PATENTS OR APPLICATIONS 19 Claims 3 Drawing Figures 312,103 5/1929 United Kingdom 123/117 A SPARK ADVANCE MECHANISM FOR IGNITION DISTRIBUTORS OF INTERNAL COMBUSTION ENGINES BACKGROUND OF THE INVENTION The present invention relates to ignition distributors for internal combustion engines, and more particularly to improvements in spark advance mechanisms of ignition distributors.

It is known to change the angular position of the breaker plate in an ignition distributor in response to the application of one or more forces. For example, the vacuum line of a vacuum advance mechanism can be connected to the carburetor at two different points. This insures that spark advances are achieved in dependency on several parameters, and such mode of spark advance not only guarantees a more satisfactory operation of the engine but also reduces the percentage of noxious ingredients in combustion products.

In certain presently known ignition distributors, the breaker plate can be turned clockwise or counterclockwise so as to achieve an advance or a delay of sparks. A drawback of such ignition distributors is that the adjusting unit or device which turns the breaker plate clockwise is invariably different from the adjusting unit or device which turns the breaker plate counterclockwise. Moreover, the power train between the breaker plate and one of the adjusting units is different from the power train between the breaker plate and the other adjusting unit. All this contributes to complexity, sensitivity and initial as well as maintenance cost of the ignition distributor.

SUMMARY OF THE INVENTION An object of the invention is to provide an ignition distributor with a novel and improved spark advance mechanism which is at least as versatile as but simpler, more rugged and less expensive than conventional spark advance mechanisms.

Another object of the invention is to provide a spark advance mechanism which can change the position of the breaker plate in response to the application of one, two or more forces so as to advance or delay the sparks in dependency on a desired number of parameters, such as the RPM of the engine, the position of the throttle, the suction in the intake manifold, the position of gear shifter means and/or others.

A further object of the invention is to provide novel and improved power trains between several adjusting units and the turnable breaker plate of an ignition distributor for internal combustion engines.

An additional object of the invention is to provide simple, compact rugged and reliable adjusting units for effecting changes in the angular position of the breaker plate.

The invention is embodied in an ignition distributor for internal combustion engines. The ignition distributor comprises a rotary driving member (e.g., a shaft which is driven by the camshaft of the engine), at least one signal generating device which is adjacent to the driving member, an actuating device which is provided on or receives torque from the driving member and is arranged to actuate the signal generating device at least once during each revolution of the driving member, a carrier which supports the signal generating device and is movable angularly about the driving member to thereby change the timing of actuation of the signal generating device by the actuating device, and regulating means for changing the angular position of the carrier.

In accordance with a feature of the invention, the regulating means comprises a displacing member (e.g., a two-armed lever) which is pivotable about a fixed axis and has a first portion operatively connected with the carriers and a second portion, a motion transmitting member (e.g., a two-armed lever) which is pivotable on the second portion of the displacing member about a second axis (this axis is preferably parallel to the fixed pivot axis of the displacing member) and has first and second arms, and first and second adjusting means which are respectively connected with the first and second arms of the motion transmitting member and are operable to pivot the displacing member through the medium of the motion transmitting member whereby the displacing member changes the angular position of the carrier. The first and/or second adjusting means may constitute a vacuum chamber with a deformable diaphragm which can change the angular position of the motion transmitting member by way of a suitable output member, an electromagnet whose armature is articulately connected with the respective arm of the motion transmitting member, a Bowden wire and/or other suitable adjusting means. It is also within the purview of the invention to provide for the first or second arm of the motion transmitting member a composite adjusting means which can change the angular position of the respective arm in response to changes in two or more parameters, such as suction in the intake manifold, the position of the throttle, the position of the gear shifter and/or others.

The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The improved ignition distributor itself, however, both as to its construction and its mode of operation, together with additional features and advantages thereof, will be best understood upon perusal of the following detailed description of certain specific embodiments with reference to the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a schematic partly elevational and partly sectional view of a portion of an ignition distributor which embodies one form of the invention;

FIG. 2 is a fragmentary elevational view of a portion of an ignition distributor which constitutes a first modification of the distributor shown in FIG. 1; and

FIG. 3 is a fragmentary elevational view of another modification of the ignition distributor shown in FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 illustrates an ignition distributor for an internal combustion engine. The ignition distributor comprises a signal generatingswitch 1 which produces signals for initiating high-voltage surges from the coil (not shown) to various spark plugs, and an actuating device 2 which actuates the switch 1 in response to rotation of a rotary driving member 3 here shown as a shaft which is driven by the camshaft (not shown) of the internal combustion engine. The direction in which the shaft 3 is rotated by the camshaft of the engine is indicated by arrow A.

The switch 1 is an interrupter switch which is mounted on a breaker plate 4 and includes a stationary contact 5 fixed to the breaker plate 4 and a movable contact 7 mounted on a contact arm 6 and biased by a customary spring (not shown) so as to normally tend to engage the fixed contact 5. The spring acts on the contact arm 6 and tends to pviot the latter counterclockwise, as viewed in FIG. 1. The pivot for the contact arm 6 on the breaker plate 4 is shown at 6a.

The actuating device 2 comprises a cam 8 which is secured to the shaft 3 and has a peripheral surface tracked by a follower 9 of the contact arm 6. A lobe 10 at the peripheral surface of the cam 8 can pivot the contact arm 6 clockwise, as viewed in FIG. 1, to thereby move the contact 7 away from the contact 5. The follower 9 and/or the contact arm 6 consists of a suitable insulating material. When the lobe 10 causes the follower 9 to move the contact 7 away from the contact 5, the switch 1 opens the circuit of the primary winding of the ignition coil whereby the secondary wiring produces a high-voltage surge which is utilized to fire a spark plug, not shown. The primary of the ignition coil is connected in circuit with a source of d-c current. The spark plug ignites the combustible mixture in the respective cylinder of the internal combustion engine. It will be seen that the switch 1 is designed to initiate the generation of firing pulses in response to opening, i.e., in response to movement of the contact 7 away from the contact 5.

Spark advances can be achieved by changing the angular position of the breaker plate 4 (and hence the angular position of the switch 1) with respect to the shaft 3 and cam 8. This insures that the firing of spark plugs is advanced or delayed, depending on the direction of angular displacement of the breaker plate 4. The spark advance mechanism comprises a plate-like carrier 11 which is connected with and supports the breaker plate 4 for the switch 1. The breaker plate 4 can be said to form part of the carrier 11. The central portion of the carrier 11 is formed with an opening 12 for the cam 8 of the actuating device 2. The carrier 11 is mounted in a housing 13 which may but need not constitute the base assembly of the ignition distributor. In accordance with a feature of the invention, the angular position of the carrier 11, breaker plate 4 and switch 1 with respect to the axis of the shaft 3 and actuating device 2 can be changed by at least one of two forces which are represented symbolically, as at B and C. The regulating means for changing the angular position of the carrier 11 in response to application of the force B and/or C comprises a motion transmitting member 14 which is a two-armed lever mounted on a pivot 17. The upper arm of the motion transmitting lever 14, as viewed in FIG. 1, is provided with a pin 15 which can be subjected to the action of the force B, and the lower arm of the lever 14 carries a similar pin 16 which can be subjected to the action of the force C.

The pivot 17 for the motion transmitting lever 14 is mounted on the upper portion or arm 18 of a twoarmed displacing lever 19 which is pivotable on a fixed pivot member 21 and has a lower portion or arm 20 which is operatively connected with the carrier 11 by a pin-and-slot connection 28, 29. The pivot 21 for the displacing lever 19 is mounted on a fixed holder 22. In the embodiment of FIG. 1, the holder 22 comprises a frame 25 which is secured to the aforementioned housing or base assembly 13 for the carrier 11 by means of screws 23, 24 or analogous fasteners. It is clear that the holder 22 can be connected to the chassis or to another stationary part of the vehicle which is driven by the internal combustion engine. The holder 22 need not even be installed under the hood of the vehicle. All that counts that the holder 22 should not move relative to the base assembly or housing 13 for the carrier 11.

In the embodiment of FIG. 1, the pivot axis of the motion transmitting lever 14 (i.e., the axis of the pivot member 17) is parallel to the pivot axis of the displacing lever 19 (pivot 21). These axes are normal to the plane of FIG. 1. Such mounting of the levers 14 and 19 simplifies the construction of the regulating means for changing the angular position ofthe carrier 11. In order to insure that the carrier 11 can be pivoted through angles of necessary magnitude, the line 26 which connects and is normal to the axes of pivots 17 and 21 is parallel to or makes an angle much greater than with a line 27 which, in neutral position of the carrier 11, connects the axes of the pins 15 and 16, i.e., the points of attack of the forces B and C upon the motion transmitting lever 14. The construction of regulating means for changing the angular position of the carrier 11 can be further simplified if the line 26 extends substantially radially of the shaft 3 when the carrier 11 assumes its neutral position. Such mounting of the levers 14 and 19 renders it possible to connect the lever 19 with the carrier 1 1 by a device as simple as the pin-andslot connection 28, 29. The longitudinal direction of the slot 29 in the lower arm 20 of the displacing lever 19 is parallel with the line 26 when the carrier 11 is allowed to assume its neutral position. It is clear that the positions of pin 28 and slot 29 can be interchanged but the provision of slot 29 in the lower arm 20 of the displacing lever 19 is preferred at this time. Savings in space can be achieved if the line 26 coincides with the line 27 in neutral position of the carrier 11, i.e., if the lines 26 and 27 make an angle of and if the direction in which the forces B and C act upon the motion transmitting lever 14 are substantially normal to the line 27. Irrespective of the selected angle between the lines 26 and 27, the arrangement is preferably such that the direction in which the force B acts upon the motion transmitting lever 14 is parallel to the direction of action of the force C. This insures an optimum utilization of the force B and/or C for angular displacement of the motion transmitting lever 14 and hence for angular displacement of the carrier 11.

The force B is applied to the pin 15 by a first adjusting unit 32 having a reciprocable output member 30 coupled to the pin 15. A similar adjusting unit 33 can apply the force C to the pin 16 by means of an output member 31. In the embodiment of FIG. 1, the force B pivots the lever 14 clockwise and the force C also pivots the lever 14 clockwise because the pins 15 and 16 are respectively provided on the upper and lower arms of the lever 14. However, the direction in which the force B acts is counter to the direction of action of the force C.

The adjusting unit 32 comprises a vacuum chamber with a vacuum diaphragm 35 which is connected with the output member 30 and is biased by a return spring 36. A nipple 37 is connected with the intake manifold of the internal combustion engine so that the position of the central portion of the diaphragm 35 is a function of pressure in the intake manifold. The intake manifold communication with a compartment or space 34 which contains the return spring 36. When the suction in the intake manifold increases, the diaphragm 35 is flexed against the opposition of the spring 36 and moves the output member 30 in a direction to the right, as viewed in FIG. 1. The extent to which the output member 30 can move in a direction to the left, as viewed in FIG. 1, is determined by a projection 39 which is provided on or secured to the output member 30 and can engage a stationary stop 41 on the holder 22.

The construction of the second adjusting unit 33 is analogous to that of the adjusting unit 32. FIG. 1 merely shows the nipple 38, the output member 31, the projection 40 on the output member 31, and the stop 42 for the projection 40. The nipple 38 is assumed to connect the compartment of the adjusting device 33 with the intake manifold of the internal combustion engine.

The stops 41, 42 cooperate with the respective projections 39, 40 to automatically locate the carrier 11 in the aforementioned neutral position when the suction in the compartments of the adjusting units 32, 33 is insufficient to flex the diaphragms against the action of the respective return springs. It will be noted that the return spring 36 and the corresponding return spring of the adjusting unit 33 are designed to move the output members 30, 31 counter to the directions indicated by arrows B and C, i.e., counter to the direction in which the lever 14 can be pivoted in response to deformation of the diaphragm in the unit 32 or 33. If desired, the projections 39, 40 may be adjustably mounted on the respective output members 30, 31 and/or the stops 41, 42 may be adjustably mounted on the holder 22.

The operation is as follows:

If the internal combustion engine is operated in the lower RPM range, the carrier 11 for the breaker plate 4 and signal generating switch 1 assumes a neutral position which is shown in FIG. 1, i.e., the projections 39, 40 respectively abut against the stops 41 and 42. The spark is neither advanced nor delayed beyond the normal timing. As a rule, the actuating device 2 then operates the switch 1 in such a way that the spark plugs are fired shortly before the corresponding pistons reach their upper end positions.

If the RPM of the engine exceeds a predetermined value, i.e., if the engine begins to operate in the partial load range, suction in the compartment to the adjusting unit 32 increases and the diaphragm 35 is flexed against the opposition of the return spring 36. The output member 30 moves in a direction to the right, as viewed in FIG. 1, and pivots the lever 14 about the pin 16 which is held against movement by the output member 31 of the adjusting unit 33. The pivot 17 causes the displacing lever 19 to pivot clockwise (i.e., in the same direction as the motion transmitting lever 14) whereby the arm causes the surface surrounding the slot 29 to change the angular position of the carrier 11 by means of the pin 28. The carrier 11 turns anticlockwise, as viewed in FIG. 1. Consequently, the spark is advanced because the follower 9 of the contact arm 6 is moved counter to the direction (arrow A) in which the cam 8 is rotated by the shaft 3. In other words, the combustible fuel-air mixture in the cylinders of the internal engine is fired earlier, i.e., well before the respective pistons reach the upper ends of their strokes, which contributes to a greater efficiency of the engine.

When the operation in the partial load range is completed, the spring 36 is free to expand and returns the projection '39 of the output member 30 into engagement with the stop 41 so that the carrier 11 reassumes its neutral position.

If the internal combustion engine is idling or coasting, suction in the compartment of the adjusting device 33 increases. The output member 31 is moved in the direction indicated by arrow C so that the projection 40 moves away from the stop 42 and the motion transmitting lever 14 is pivoted clockwise about the axis of the pin 15 which is held against movement by the output member 30. The member 17 pivots the displacing lever 19 counterclockwise, as viewed in FIG. 1, whereby the carrier 11 pivots clockwise and delays the firing of spark plugs because the follower 9 is caused to move in the direction indicated by arrow A. Thus, the timing of the firing of spark plugs is such that the combustible mixture in the cylinders is fired at the time when or immediately before the pistons reach their upper end positions. This insures a more satisfactory combustion of the mixture and reduces the percentage of noxious ingredients in combustion products.

The carrier 11 automatically reassumes its neutral position when the internal combustion angle ceases to idle or coast; the spring in the adjusting unit 33 then causes the output member 31 to return the projection 40 into engagement with the stop 42.

If the suction in the compartments of the adjusting units 32 and 33 is increased simultaneously, the angular displacement of carrier 11 corresponds to the difference of the extent of lengthwise displacement of the output members 30, 31, i.e., the spark is advanced if the extent of displacement of the output member 30 is greater than that of the output member 31, and the spark is delayed if the extent of displacement of the 7 output members 30, 31 is such that the lever 14 pivots clockwise.

FIG. 2 illustrates a portion of a second ignition distributor wherein all such parts which are clearly analogous to or identical with the corresponding parts of the ignition distributor of FIG. 1 are denoted by similar reference characters. The difference is that the forces B and C cause the carrier 11 (not shown in FIG. 2) to change its angular position in a single direction, namely, to delay the spark. As shown, the upper pin 15 of the motion transmitting lever 14 is moved in a direction to the left when the diaphragm in the adjusting unit 32 is displaced whereby the output member 30 causes the lever 14 to pivot about the pin 16 so that the member 17 pivots the displacing lever 19 counterclockwise and the carrier 11 turns clockwise. When the diaphragm of the adjusting unit 33 causes the output member 31 to move in a direction to the left, as viewed in FIG. 2, the lever 14 pivots about the pin 15 and causes the pivot 17 to turn the displacing lever 19 counterclockwise, i.e., the carrier 11 again rotates clockwise to delay the firing of spark plugs.

The structure of FIG. 2 is employed when the adjustment of the carrier 11 in a predetermined direction should take place in two successive stages. For example, the adjusting unit 33 can change the angular position of the carrier 11 in a first step so that the carrier 11 causes the switch 1 to delay the firing of spark plugs. If the suction in the compartment of the adjusting unit 32 is thereupon intensified, the lever 19 again pivots counterclockwise and the firing of spark plugs is delayed still further. As mentioned above, the movement of output member 30 in a direction to the left, as

viewed in FIG. 2, causes the motion transmitting lever 14 to pivot counterclockwise about the axis of the pin 16 whereby the displacing lever 19 moves counterclockwise under the action of the pivot 17. Thus the lever 19 turns on the pivot 21 and moves the carrier 11 in a clockwise direction to thereby delay the spark.

The construction of FIG. 2 is desirable in many types of internal combustion engines because it insures rapid heating of reactors or catalysts which are used for secondary treatment of combustion products. Thus, the engine is heated up more rapidly than with advanced spark and the reactors or catalysts become effective after a short interval of heating.

FIG. 2 further indicates that the displacing lever 19 can be pivoted in response to the application of more than two forces. The forces B and C of FIG. 2 tend to delay the spark whereas the forces D and E (indicated by broken-line arrows) tend to advance the spark by causing the lever 19 to pivot clockwise. The force D can act on the motion transmitting lever by way of the pin and the force E can act by way of the pin 16. The forces D and E can be applied simultaneously or one after the other, depending upon whether or not the spark is to be advanced in one or more stages.

FIG. 3 shows a third ignition distributor wherein all such parts which are identical with or clearly analogous to the corresponding parts of the ignition distributor of FIG. 1 are again denoted by similar reference characters. The main difference is that the pin 15 of the motion transmitting lever 14 can pivot the displacing lever 19 in response to the application of several forces (e.g., in response to the application of two forces indicated by arrows F and G. It is clear that the output member 31 of FIG. 3 can be replaced or actuated by a mechanism similar to that shown in FIG. 3 to change the position of the output member 30. Furthermore, the mechanism shown in the upper part of FIG. 3 can be used to move the output member 31 and the output member 30 can be moved in the same way as shown in FIG. 1.

The adjusting unit for moving the output member 30 comprises a second two-armed displacing lever 44 which is pivotable on the frame 25, as at 46 and has a lower portion or arm 43 articulately connected with the output member 30 by a pivot pin 43a. The upper portion or arm 45 of the lever 44 carries a second motion transmitting lever 47 which is analogous to the lever 14 and is mounted on the'arm 45 by means of a pivot 50. The upper and lower arms of the lever 47 respectively carry pins 48, 49 for output members 53, 54 which transmit the forces F and G.

The axes of pivots 46 and 50 for the levers 44 and 47 are preferably parallel to each other and normal to the plane of FIG. 3. Also, and as explained in connection with FIG. 1, the line 51 which connects and is normal to the axes of pivots 46 and 50 is parallel to or makes an angle well in excess of 90 degrees with the line 52 which connects the axes of pins 48 and 49 whenever the carrier assumes its neutral position. This insures that the carrier (not shown in FIG. 3) can be turned through an angle which is large enough to guarantee a desirable advance or delaying of the spark. The lines 51 and 52 can be parallel to each other in the neutral position of the carrier. Such mounting of the levers 44 and 47 further insures that the forces F and G can be used to maximum extent to change the angular position of the carrier. A space-saving design can be obtained if, in the neutral position of the carrier, the direction in which the forces F and G act on the lever 47 is normal to the line 51 and/or 52. The line 26 is preferably parallel to the line 51 in neutral position of the carrier.

In the embodiment of FIG. 3, the direction of action of the force F is parallel to the direction of action of the force G. The two forces act on the lever 47 in the same direction, i.e., to the left, as viewed in FIG. 3. The force F is furnished by an additional adjusting unit in the form of an electromagnet 55 having a reciprocable armature 56 which is articulately connected with the output member 53, as at 53a. For example, the electromagnet 55 can be energized in response to rotation of the crankshaft of the internal combustion engine and is energized sufficiently to displace the output member 53 when the speed of the crankshaft reaches a certain RPM.

The force G is assumed to be furnished by a second additional adjusting unit here shown as a Bowden wire 57 which is surrounded by a tubular sheath 58 secured to the holder 22. The other end of the Bowden wire can be connected with the throttle (not shown) in the intake manifold of the internal combustion engine or with the gear shifter means of the vehicle. The arrangement is such that the wire 57' applies to the output member 54 a force G when the throttle in the intake manifold changes its position, i.e., when the rate at which the cylinders receive a fuel air mixture is changed, or when the driver operates the gear shifter.

The operation of the ignition distributor of FIG. 3 is as follows:

If the electromagnet 55 is energized and the armature 56 applies the force F to the output member 53, the motion-transmitting lever 47 is pivoted counterclockwise about the pin 49 whereby the pivot turns the displacing lever 44 in a counterclockwise direction, as

viewed in FIG. 3. The output member 30 moves in a direction to the right and pivots the motion transmitting lever 14 in a clockwise direction (about the pin 16). The displacing lever 19 also pivots clockwise and turns the carrier 11 in a counterclockwise direction to advance the spark accordingly.

If the application of the force F is terminated and the Bowden wire 57 applies to the output member 54 a force G, the motion transmitting lever 47 pivots clockwise about the pin 48 and the pivot 50 turns the displacing lever 44 counterclockwise, as viewed in FIG. 3. The output member 30 moves in a direction to the right and pivots the motion transmitting lever 14 clockwise about the pin 16. The pivot 17 turns the displacing lever 19 clockwise and the carrier 11 is adjusted to advance the spark.

The force F can be applied simultaneously with the force G. This is desirable if it becomes necessary to advance the spark beyond the extent which can be achieved by the application of the force F or G alone.

It is equally possible to mount the electromagnet in such a way that the force F tends to pivot the lever 47 in a clockwise direction or to mount the Bowden wire 57 in such a way that the force G tends to pivot the lever 47 in a counterclockwise direction. The force F or G then serves to delay the spark. Still further, the adjusting unit including the electromagnet 55 and/or the wire 57 can be replaced by a vacuum chamber such as the vacuum chamber 32 or 33 of FIG. 1.

The output member 31 of FIG. 1 can be moved in the same way as described in connection with FIG. 1.

Without further analysis, the foregoing will so fully reveal the gist of the present invention'that others can, by applying current knowledge, readily adapt it for various applications without omitting features which fairly constitute essential characteristics of the generic and specific aspects of my contribution to the art and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the claims.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended:

1. In an ignition distributor for internal combustion engines, a combination comprising a rotary driving shaft; at least one signal generating device adjacent to said driving shaft; an actuating device receiving torque from said driving shaft and arranged to actuate said signal generating device at least once during each revolution of said driving shaft; a carrier for said signal generating device, said carrier being movable angularly from a neutral position about said driving shaft to thereby change the timing of actuation of said signal generating device; and regulating means for changing the angular position of said carrier, including a displacing member pivotable about a fixed pivot axis and having a first portion operatively connected with said carrier and a second portion, a motion transmitting member mounted on said second portion pivotable about a second pivot axis and having first and second arms, and first and second adjusting members respectively connected at first and second points to the first and second arms and operable to pivot said displacing member through the medium of said motion transmitting member, whereby said displacing member changes the angular position of said carrier, a first line which is normal to and intersects said fixed pivot axis and said second pivot axis and a second line connecting said first and said second points extent when said carrier is in said neutral position, substantially in the same direction and in radial direction of said driving shaft, and the direction of the forces produced by said adjusting members on said first and second points being substantially normal to both of said lines.

2. A combination as defined in claim 1, wherein said signal generating device comprises a switch and said driving member is a shaft, said actuating device comprising cam means provided on and rotatable with said shaft.

3. A combination as defined in claim 1, wherein said displacing member is a first lever having first and second arms which respectively constitute said first and second portions and said motion transmitting member is a second lever, said second pivot axis being parallel to said fixed pivot axis.

4. A combination as defined in claim 1, wherein said carrier normally assumes a neutral position and said first adjusting means comprises a first output member operatively connected with said first arm at a first point, said second adjusting means comprising a second output member operatively connected with said second arm at second point, a first line.

5. A combination as defined in claim 4, wherein each of said output members is substantially normal to said first line in said neutral position of said carrier.

6. A combination as defined in claim 4, wherein said output members are arranged to transmit to the respective arms of said motion transmitting member first and second forces which are at least substantially parallel to each other.,.-

7. A combination as defined in claim I, wherein each of said adjusting means is arranged to'pivot said motion transmitting member in a predetermined direction.

8. A combination as defined in claim 1, wherein said first and second adjusting means are arranged to pivot said motion transmitting member in opposite directions.

9. A combination as defined in claim 1, further comprising a pin-and-slot connection between said carrier and said first portion of said displacing member.

10. A combination as defined in claim 9, wherein said connection comprises a pin on said carrier and an elongated slot receiving said pin and provided in said first portion of said displacing member.

11. A combination as defined in claim 10, wherein said carrier normally assumes a neutral position and a line connecting said fixed pivot axis with said second pivot axis is parallel to the longitudinal direction of said slot in said neutral position of said carrier.

12. A combination as defined in claim 1, further comprising stop means for limiting the extent of pivotal movement of said motion transmitting member.

13. A combination as defined in claim 1, wherein at least one of said adjusting means comprises a vacuum chamber wherein the pressure varies as a function of changes in the rate of admission of fuel-air mixture to the cylinder or cylinders of the engine.

14. In an ignition distributor for internal combustion engines, a combination comprising a rotary driving member; at least one signal generating device adjacent to said driving member; an actuating device receiving torque from said driving member and arranged to actuate said signal generating device at least once during each revolution of said driving member; a carrier for said signal generating device, said carrier being movable angularly about said driving member to thereby change the timing of actuation of said signal generating device; and regulating means for changing the angular position of said carrier, including a displacing member pivotable about a fixed axis and having a first portion operatively connected with said carrier and a second portion, a motion transmitting member pivotable on said second portion of said displacing member and having first and second arms, and first and second adjusting means respectively connected with said first and second arms and operable to pivot said displacing member through the medium of said motion transmitting member, at least one of said adjusting members comprising a second displacing member pivotable about a second fixed axis and having a first portion operatively connected with the respective arm of said motion transmitting member and a second portion, a second motion transmitting member pivotable on said second portion of said second displacing member about a further axis and having first and second arms, and first and second additional adjusting means respectively connected with said first and second arms of said second motion transmitting member and operable to pivot said second motion transmitting member whereby said second motion transmitting member pivots said first mentioned motion transmitting member through the medium of said second displacing member.

15. A combination as defined in claim 14, wherein said second fixed axis is parallel to said further axis.

16. A combination as defined in claim 14, wherein said first and second additional adjusting means are respectively connected to said first and second arms of said second motion transmitting member at first and second points and said carrier normally assumes a neutral position, a first line connecting said second fixed axis with said further axis making with a second line which connects said first and second points an angle other than 90 degrees when said carrier assumes said neutral position.

17. A combination as defined in claim 16, wherein said first and second lines are parallel to each other in said neutral position of said carrier.

18. A combination as defined in claim 17, wherein said first and second additional adjusting means are arranged to apply to the respective arms of said second motion transmitting member first and second forces which are substantially normal to said first and second lines in said neutral position of said carrier.

19. A combination as defined in claim 14, wherein said carrier normally assumes a neutral position and said first and second adjusting means respectively comprise first and second output members respectively arranged to apply first and second forces to first and second points of said first and second arms of said first mentioned motion transmitting member, said first and second additional adjusting means comprising third and fourth output members respectively arranged to apply third and fourth forces to third and fourth points of said first and second arms of said second motion transmitting member, a line connecting said first and second points being parallel with a line connecting said third and fourth points in said neutral position of said carrier. 

1. In an ignition distributor for internal combustion engines, a combination comprising a rotary driving shaft; at least one signal generating device adjacent to said driving shaft; an actuating device receiving torque from said driving shaft and arranged to actuate said signal generating device at least once during each revolution of said driving shaft; a carrier for said signal generating device, said carrier being movable angularly from a neutral position about said driving shaft to thereby change the timing of actuation of said signal generating device; and regulating means for changing the angular position of said carrier, including a displacing member pivotable about a fixed pivot axis and having a first portion operatively connected with said carrier and a second portion, a motion transmitting member mounted on said second portion pivotable about a second pivot axia and having first and second arms, and first and second adjusting members respectively connected at first and second points to the first and second arms and operable to pivot said displacing member through the medium of said motion transmitting member, whereby said displacing member changes the angular position of said carrier, a first line which is normal to and intersects said fixed pivot axis and said second pivot axis and a second line connecting said first and said second points extent when said carrier is in said neutral position, substantially in the same direction and in radial direction of said driving shaft, and the direction of the forces produced by said adjusting members on said first and second points being substantially normal to both of said lines.
 2. A combination as defined in claim 1, wherein said signal generating device comprises a switch and said driving member is a shaft, said actuating device comprising cam means provided on and rotatable with said shaft.
 3. A combination as defined in claiM 1, wherein said displacing member is a first lever having first and second arms which respectively constitute said first and second portions and said motion transmitting member is a second lever, said second pivot axis being parallel to said fixed pivot axis.
 4. A combination as defined in claim 1, wherein said carrier normally assumes a neutral position and said first adjusting means comprises a first output member operatively connected with said first arm at a first point, said second adjusting means comprising a second output member operatively connected with said second arm at second point, a first line.
 5. A combination as defined in claim 4, wherein each of said output members is substantially normal to said first line in said neutral position of said carrier.
 6. A combination as defined in claim 4, wherein said output members are arranged to transmit to the respective arms of said motion transmitting member first and second forces which are at least substantially parallel to each other.
 7. A combination as defined in claim 1, wherein each of said adjusting means is arranged to pivot said motion transmitting member in a predetermined direction.
 8. A combination as defined in claim 1, wherein said first and second adjusting means are arranged to pivot said motion transmitting member in opposite directions.
 9. A combination as defined in claim 1, further comprising a pin-and-slot connection between said carrier and said first portion of said displacing member.
 10. A combination as defined in claim 9, wherein said connection comprises a pin on said carrier and an elongated slot receiving said pin and provided in said first portion of said displacing member.
 11. A combination as defined in claim 10, wherein said carrier normally assumes a neutral position and a line connecting said fixed pivot axis with said second pivot axis is parallel to the longitudinal direction of said slot in said neutral position of said carrier.
 12. A combination as defined in claim 1, further comprising stop means for limiting the extent of pivotal movement of said motion transmitting member.
 13. A combination as defined in claim 1, wherein at least one of said adjusting means comprises a vacuum chamber wherein the pressure varies as a function of changes in the rate of admission of fuel-air mixture to the cylinder or cylinders of the engine.
 14. In an ignition distributor for internal combustion engines, a combination comprising a rotary driving member; at least one signal generating device adjacent to said driving member; an actuating device receiving torque from said driving member and arranged to actuate said signal generating device at least once during each revolution of said driving member; a carrier for said signal generating device, said carrier being movable angularly about said driving member to thereby change the timing of actuation of said signal generating device; and regulating means for changing the angular position of said carrier, including a displacing member pivotable about a fixed axis and having a first portion operatively connected with said carrier and a second portion, a motion transmitting member pivotable on said second portion of said displacing member and having first and second arms, and first and second adjusting means respectively connected with said first and second arms and operable to pivot said displacing member through the medium of said motion transmitting member, at least one of said adjusting members comprising a second displacing member pivotable about a second fixed axis and having a first portion operatively connected with the respective arm of said motion transmitting member and a second portion, a second motion transmitting member pivotable on said second portion of said second displacing member about a further axis and having first and second arms, and first and second additional adjusting means respectively connected with said first and second arms of said second motion transmittinG member and operable to pivot said second motion transmitting member whereby said second motion transmitting member pivots said first mentioned motion transmitting member through the medium of said second displacing member.
 15. A combination as defined in claim 14, wherein said second fixed axis is parallel to said further axis.
 16. A combination as defined in claim 14, wherein said first and second additional adjusting means are respectively connected to said first and second arms of said second motion transmitting member at first and second points and said carrier normally assumes a neutral position, a first line connecting said second fixed axis with said further axis making with a second line which connects said first and second points an angle other than 90 degrees when said carrier assumes said neutral position.
 17. A combination as defined in claim 16, wherein said first and second lines are parallel to each other in said neutral position of said carrier.
 18. A combination as defined in claim 17, wherein said first and second additional adjusting means are arranged to apply to the respective arms of said second motion transmitting member first and second forces which are substantially normal to said first and second lines in said neutral position of said carrier.
 19. A combination as defined in claim 14, wherein said carrier normally assumes a neutral position and said first and second adjusting means respectively comprise first and second output members respectively arranged to apply first and second forces to first and second points of said first and second arms of said first mentioned motion transmitting member, said first and second additional adjusting means comprising third and fourth output members respectively arranged to apply third and fourth forces to third and fourth points of said first and second arms of said second motion transmitting member, a line connecting said first and second points being parallel with a line connecting said third and fourth points in said neutral position of said carrier. 